The use of optical communication is ever increasing with a high growth rate in the areas that require a very low data communication latency, such as financial markets.
However, current optical communications include fiber optics as the medium of communication. Since the fibers have a typical refractive index n=1.50, it suffers from latency due to such fiber optic medium. Moreover, the long distance/range optical communication systems are typically laid down under the seas or oceans and thus suffer from external physical interferences, for example, interferences from the ships dragging anchors over such fibers. Furthermore, natural disasters can also disrupt connections, and the ability to rapidly reconfigure a communication network to reconnect the affected areas can be extremely valuable. In addition to the underserved markets, the major global telecom carriers of significant and growing wholesale bandwidth have needs for backup and replacement bandwidth to maintain Quality of Service agreements.
Additionally, space based communication systems suffer from limited bandwidth, high latency (due to long free space ranges), and long deployment time. For example, Geostationary Earth Orbit (GEO) communication satellites have inherently high latency, while other satellite communication networks suffer from some combination of limited worldwide connectivity, low bandwidth, or cost. The GEO satellites offer coverage of a reasonably large fraction of the Earth per satellite but have long communication paths (˜36,000 km) resulting in a signal latency of at least 120 msec per path. Moreover, multiple bounces may be required to provide routing, and connection between ground sites not within the footprint of the same satellite may require ground connections. Additionally, GEO communication satellites are currently restricted to Radio Frequency (RF) signals, which limit available bandwidth to a range of hundreds of MHz to a few GHz. Furthermore, multiple beams need to be used to provide relatively high total throughput per satellite (72 beams at 48 Mbps is typical, for 3.4 Gbps per satellite).
Similarly, the Iridium™ constellation simply doesn't have the bandwidth to address the same market. Iridium's™ Low Earth Orbit (LEO) constellation has an altitude of about 780 km, which limits access per satellite. Accordingly, a constellation of 66 active satellites is used to provide 24/7 coverage of the entire world. Use of L-band in LEO constellation limits the bandwidth of satellite phones to less than 1 Mbps. Gateway links offer 10 Mbps of bandwidth to a few selected locations. Moreover, inter-satellite links are RF, with substantially limited bandwidth.